# feof

From cppreference.com
< c‎ | io

Defined in header ``<stdio.h>`` |  |
int feof( FILE *stream ); |  |

Checks if the end of the given file stream has been reached.

### Parameters

stream | - | the file stream to check

### Return value

nonzero value if the end of the stream has been reached, otherwise ​0​

### Notes

This function only reports the stream state as reported by the most recent I/O operation, it does not examine the associated data source. For example, if the most recent I/O was a fgetc, which returned the last byte of a file, `feof` returns zero. The next fgetc fails and changes the stream state to end-of-file. Only then `feof` returns non-zero.

In typical usage, input stream processing stops on any error; `feof` and ferror are then used to distinguish between different error conditions.

### Example

Run this code

    #include <stdio.h>
    #include <stdlib.h>

    int main(void)
    {
        const char* fname = "/tmp/unique_name.txt"; // or tmpnam(NULL);
        int is_ok = EXIT_FAILURE;

        FILE* fp = fopen(fname, "w+");
        if (!fp)
        {
            perror("File opening failed");
            return is_ok;
        }
        fputs("Hello, world!\n", fp);
        rewind(fp);

        int c; // note: int, not char, required to handle EOF
        while ((c = fgetc(fp)) != EOF) // standard C I/O file reading loop
            putchar(c);

        if (ferror(fp))
            puts("I/O error when reading");
        else if (feof(fp))
        {
            puts("End of file is reached successfully");
            is_ok = EXIT_SUCCESS;
        }

        fclose(fp);
        remove(fname);
        return is_ok;
    }

Possible output:

    Hello, world!
    End of file is reached successfully

### References

- C11 standard (ISO/IEC 9899:2011):

  - 7.21.10.2 The feof function (p: 339)

- C99 standard (ISO/IEC 9899:1999):

  - 7.19.10.2 The feof function (p: 305)

- C89/C90 standard (ISO/IEC 9899:1990):

  - 4.9.10.2 The feof function

### See also

clearerr | clears errors (function)
perror | displays a character string corresponding of the current error to stderr (function)
ferror | checks for a file error (function)
C++ documentation for feof

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